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基于IPTA技术的广州市2017—2020年地铁沿线沉降监测

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测绘与空间地理信息 2024年第3期47卷 58-60,64页

作者：李晓诗孙敏杜亚男刘清瑶罗澍然广州大学地理科学与遥感学院广东广州510006 中南大学地球科学与信息物理学院湖南长沙410083

干涉点目标分析技术(IPTA)是一种常用的地表形变监测技术,能够克服大气延迟、时空失相关的影响,获取高精度的监测数据。本文采用IPTA技术对覆盖广州市2017年5月至2020年5月期间的85景Sentinel-1A影像进行处理,获取了广州市的平均形变速... 详细信息

干涉点目标分析技术(IPTA)是一种常用的地表形变监测技术,能够克服大气延迟、时空失相关的影响,获取高精度的监测数据。本文采用IPTA技术对覆盖广州市2017年5月至2020年5月期间的85景Sentinel-1A影像进行处理,获取了广州市的平均形变速率信息。同时,本文还分析了广州市及其地铁沿线形变的空间分布特点。结果显示:广州市地铁沿线的整体地表形变较为稳定,沉降主要集中在6号线沿线,最大的沉降漏斗位于柯木塱站,沉降速率达到了-39.5 mm/yr。结合实地考察结果,IPTA技术能够为大范围城市地铁沿线的沉降监测提供可靠的信息支撑。

关键词：地铁沉降监测 IPTA Sentinel-1A

Fabrication,Microstructure and Mechanical Properties of in situ GNPs Reinforced Magnesium Matrix Composites

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 561-569页

作者： Peitang Zhao Xuejian li Hailong Shi xiaoshi Hu Chunlei Zhang Chao Xu Xiaojun Wang The 38th Research Institute of China Electronics Technology Group Corporation Hefei 230088China National Key Laboratory of Precision Hot Processing of Metal Harbin Institute of TechnologyHarbin 150001China

Graphene reinforced magnesium matrix composites have wide applications in automotive,electronics,aerospace and military fields due to the fascinating mechanical ***,it is difficult to realize the high strength and ductility *** this work,the in situ liquid-state method was utilized to prepare GNPs/Mg6Zn composites via CO_(2)/Mg chemical *** strength of the GNPs/Mg6Zn composites was improved with increasing content of the ***,the composites also exhibit a notable plastic deformation stage,and especially the ductility of 0.12 GNPs/Mg6Zn composites reaches 27.6%.Therefore,this novel preparation method has great potential application for fabricating Mg matrix composites with high strength and high ductility.

关键词： Magnesium matrix composite In situ composite Microstructure Mechanical properties

Structure and coalbed methane occurrence in tectonically deformed coals

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Science China Earth Sciences 2012年第10期55卷 1755-1763页

作者： HOU Quanlin li HuiJun FAN JunJia JU YiWen WANG TianKai li xiaoshi WU YuDong Key Laboratory of Computational Geodynamics CASCollege of Earth ScienceGraduate University of Chinese Academy of SciencesBeijing 100049China Research Institute of Petroleum Exploration & Development State Key laboratory of Enhanced Oil RecoveryRIPED Petro ChinaBeijing 100083China Institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China

Research on structure of tectonically deformed coals(TDC) is a key issue in coal and gas outburst prevention and coalbed methane(CBM) *** paper presents a summary on the research progress in TDC's structural-genetic classification,tectonic strain influence on coal microstructure,coal porosity system,coal chemical structure and constituents,and their relationship with the excess coalbed *** studies suggested that tectonic deformation had significant influence on coal microstructure,coal super microstructure,and even chemical macromolecular *** main mechanisms of coal deformation are the tectonic stress degradation and polycondensation metamorphism(dynamical metamorphism).Besides,under different deformation mechanisms,the ultra-and micro-structure and chemical constituents of TDC presented distinct *** on these achievements,we propose one possible evolutionary trend of TDC with different deformation mechanisms,and suggest that the coal and gas outburst in the TDC,especially in the mylonitic coals,may be not only controlled by geological structure,but also influenced by the tectonic stress degradation of ductile ***,further study on TDC should be focused on the controlling mechanism of deformation on structure and composition of coal,generation conditions and occurrence state of excess coalbed methane from deformation mechanism of coal.

关键词：微观结构煤层气构造煤香港贸易发展局动力变质作用煤与瓦斯突出变形机制化学成分

Response of Macromolecular Structure to Deformation in Tectonically Deformed Coal

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Acta Geologica Sinica(English Edition) 2013年第1期87卷 82-90页

作者： li xiaoshi JU Yiwen HOU Quanlin FAN Junjia Key Laboratory of Computational Geodynamics Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences PetroChina Research Institute of Petroleum Exploration and Development Key Laboratory of Basin Structure and Petroleum Accumulation

The structural evolution of tectonically deformed coals （TDC） with different deformational mechanisms and different deformational intensities are investigated in depth through X-ray diffraction （XRD） analysis on 31 samples of different metamorphic grades （R ： 0.7%-3.1%） collected from the Huaibei coalfield. The results indicated that there are different evolution characteristics between the ductile and brittle deformational coals with increasing of metamorphism and deformation. On the one hand, with the increase of metamorphism, the atomic plane spacing （d002） is decreasing at step velocity, the stacking of the BSU layer （Lc） is increasing at first and then decreasing, but the extension of the BSU layer （La） and the ratio of La/Lc are decreasing initially and then increasing. On the other hand, for the brittle deformational coal, d002 is increasing initially and then decreasing, which causes an inversion of the variation of Lc and La under the lower-middle or higher-middle metamorphism grade when the deformational intensity was increasing. In contrast, in the ductile deformational coals, d002 decreased initially and then increased, and the value of L~ decreased with the increase of deformational intensity. But the value of La increased under the lower-middle metamorphism grade and increased at first and then decreased under the higher-middle metamorphism grade. We conclude that the degradation and polycondensation of TDC macromolecular structure can be obviously impacted during the ductile deformational process, because the increase and accumulation of unit dislocation perhaps transforms the stress into strain energy. Meanwhile, the brittle deformation can transform the stress into frictional heat energy, and promote the metamorphism and degradation as well. It can be concluded that deformation is more important than metamorphism to the differential evolution of the ductile and brittle deformational coals.

关键词： tectonically deformed coal X-ray diffraction deformational mechanism deformationalintensity macromolecular structure

A New Parameter as an Indicator of the Degree of Deformation of Coals

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Journal of Earth Science 2017年第2期28卷 358-366页

作者： Mingming Wei Yiwen Ju Quanlin Hou Guochang Wang liye Yu Wenjing Zhang xiaoshi li Key Laboratory of Computational Geodynamics CASCollege of Earth ScienceUniversity of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry of CASGuangzhou 510640China

The deformation of coal is effected by thermal effect, pressures and tectonic stress, and the tectonic stress is the principal influence factor. However, the proposition of a useful quantitative index that responds to the degree of deformation of coals quantitatively or semi-quantitatively has been a long-debated issue. The vitrinite reflectance ellipsoid, that is, the reflectance indication surface（RIS） ellipsoid is considered to be a strain ellipsoid that reflects the sum of the strain increment caused by stress in the process of coalification. It has been used to describe the degree of deformation of the coal, but the effect of the anisotropy on the RIS ellipsoid has not yet been considered with regards to non-structural factors. In this paper, Wei＇s parameter（ε） is proposed to express the deformation degree of the strain ellipsoid based on considering the combined influence of thermal effect, pressure and tectonic stress. The equation is as follows： ε=√[（ε_1-ε_0）~2＋（ε_2-ε_0）~2＋（ε_3-ε_0）~2]/3, where ε_1=lnR_（max）, ε_2=lnR_（int）, ε_3=lnR_（min）, and ε_0=（ε_1＋ε_2＋ε_3）/3. Wei＇s parameter represents the distance from the surface to the spindle of the RIS logarithm ellipsoid; thus, the degree of deformation of the strain ellipsoid is indicated quantitatively. The formula itself, meanwhile, represents the absolute value of the degree of relative deformation and is consequently suitable for any type of deformation of the strain ellipsoid. Wei＇s parameter makes it possible to compare degrees of deformation among different deformation types of the strain ellipsoid. This equation has been tested in four types of coal： highly metamorphic but weakly deformed coal of the southern Qinshui Basin, highly metamorphic and strongly deformed coal from the Tianhushan coal mining area of Fujian, and medium metamorphic and weakly or strongly deformed coal from the Huaibei Coalfield. The results of Wei＇s parameters are consistent with the actual deformation degrees of the coal reservoirs

关键词： Wei's parameter(ε) deformation degree of coals quantitative index vitrinite reflectance ellipsoid

New research progress on the ultrastructure of tectonically deformed coals

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Progress in Natural Science:Materials International 2009年第11期19卷 1455-1466页

作者： Yiwen Ju,xiaoshi li Laboratory of Computational Geodynamics,College of Earth Science,Graduate University of Chinese Academy of Sciences,Beijing 100049,China Laboratory of Computational Geodynamics College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China

The structure of tectonically deformed coals shows some characteristics and regulations on the ultra-scale when influenced by different factors such as temperature,pressure and directional *** of the macromolecular structure may induce changes in the nano-scale pore structure,which are very important for gas adsorption and *** geological impact of different mechanisms of deformation on different types of ultrastructure of tectonically deformed coals is not only of significance as a topic for scientific research, but also in studying environments of metamorphism-deformation at differing metamorphic *** research is also very important in studying the accumulation and occurrence conditions of coalbed methane gas,mechanisms of coal and gas outbursts,predictions of coalbed methane resources and dangers of coal and gas *** paper analyzes current research,within China and other countries, in the ultrastructure of tectonically deformed *** research includes(1) structural models of tectonically deformed coals;(2) the relationship between ultrastructure and stress;(3) the structure of tectonically deformed coals and its strain *** results are also based on our own experiments including vitirnite reflectance(Ro,max),X-ray diffraction(XRD) and nuclear magnetic resonance (NMR(CP/MAS + TOSS)).We discuss the important effects of the structure of tectonically deformed coals and their physical properties,and then point out some problems concerning the research progress of tectonically deformed coals.

关键词： Tectonically deformed coals Ultrastructure Pore structure Tectonic stress Strain environment

Micro-structural evolution and their effects on physical properties in different types of tectonically deformed coals

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International Journal of Coal Science & Technology 2014年第3期1卷 364-375页

作者： Yiwen Ju Kray Luxbacher xiaoshi li Guochang Wang Zhifeng Yan Mingming Wei liye Yu Laboratory of Computational Geodynamics College of Earth ScienceUniversity of Chinese Academy of SciencesBeijing 100049China Department of Mining&Minerals Engineering Virginia TechBlacksburgVA 24061USA

The macromolecular structure of tectonically deformed coals(TDC)may be determined by the deformation mechanisms of *** of the macromolecular structure change the pore structure of TDC and thereby impact physical properties such as porosity and *** study focuses on structure and properties of TDC from the Huaibei and Huainan coal mining areas of southern North *** between the macromolecular structure and the pore structure of TDC were analyzed using techniques such as X-ray diffraction,high-resolution transmission electron microcopy,and the low-temperature nitrogen *** results indicated that the directional stress condition can cause the arrangement of basic structural units(BSU)more serious and ***,the orientation is stronger in ductile deformed coal than in brittle deformed *** deformation directly influences the macromolecular structure of coal and consequently results in dynamic *** the size of BSU in brittle deformed coal increases more slowly than in ductile deformed coal,frictional heating and stress-chemistry of shearing areas might play a more important role,locally altering coal structure under stress,in brittle deformed *** energy is more significant in increasing the ductile deformation of ***,mesopores account for larger percentage of the nano-scale pore volume in brittle deformed coals,while mesopores volume in ductile deformed coal diminishes rapidly along with an increase in the proportion of micropores and *** research also approved that the deformations of macromolecular structures change nano-scale pore structures,which are very important for gas adsorption and pervasion space for ***,the exploration and development potential of coal bed methane is promising for reservoirs that are subjected to a certain degree of brittle deformation(such as schistose structure coal,mortar structure coal and cataclastic structure co

关键词： Tectonically deformed coals Formation mechanisms Macromolecular structure Pore structure Micro-structured evolution Coal bed methane

Leaching kinetics of fluorine during the aluminum removal from spent li-ion battery cathode materials

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Journal of Environmental Sciences 2024年第4期138卷 312-325页

作者： Shengjie li Jianxin Zhu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The high content of aluminum(Al)impurity in the recycled cathode powder seriously affects the extraction efficiency of Nickel,Cobalt,Manganese,and lithium resources and the actual commercial value of recycled materials,so Al removal is crucially important to conform to the industrial standard of spent li-ion battery cathode *** this work,we systematically investigated the leaching process and optimum conditions associated with Al removal from the cathode powder materials collected in a wet cathode-powder peeling and recycling production line of spent li-ion batteries(liBs).Moreover,we specifically studied the leaching of fluorine(F)synergistically happened along with the removal process of Al,which was not concerned about in other studies,but one of the key factors affecting pollution prevention in the recovery *** mechanism of the whole process including the leaching of Al and F from the cathode powder was indicated by using NMR,FTIR,and XPS,and a defluoridation process was preliminarily investigated in this *** leaching kinetics of Al could be successfully described by the shrinking core model,controlled by the diffusion process and the activation energy was 11.14 kJ/***,the leaching of F was attributed to the dissolution of liPF6and decomposition of PVDF,and the kinetics associated was described by Avrami *** interaction of Al and F is advantageous to realize the defluoridation to some *** is expected that our investigation will provide theoretical support for the large-scale recycling of spent liBs.

关键词： Al removal F leaching Cathode powder Heating alkali leaching Leaching kinetics

Additives strategies to improving cycling stability of li metal batteries by modifying electrode electrolyte interphases

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Progress in Natural Science:Materials International 2024年第2期34卷 338-344页

作者： Yuan li Pengfei Huang Chunyu Cui Xiaoyuan Ma li Chen Zekun li linhai li Yuhong Tian School of Biological and Chemical Engineering Guangxi University of Science and Technology School of College of Chemistry and Chemical Engineering Hunan University Isky Future Energy Institute

li metal batteries（LMBs） have attracted much attention due to the ultra-high theoretical capacity of the li metal anode（LMA）.However,the uncontrollable dendrites growth and low coulombic efficiency hinder their practical ***,we explore 3,5-difluoropyridine（2F-BD） as a novel electrolyte additive to enable highperformance *** 2F-BD additive participates in and modifies the solvation structure of li ions by reducing the coordinated number of PF6-at the electrode surface,leading to the formation of a liF and li3N-rich solid electrolyte interphase（SEI）.The liF component increases the robustness of SEI and suppresses the formation of li dendrites,while the li3N component facilitates the transportation and reaction kinetics of li *** a result,the li‖li symmetric cell presents a stable cycling performance of up to 500 h at a current density of 1 mA *** coupling with liFePO4cathode,the obtained full cell achieves high specific capacities of 106.06 mA h g-1and 84.98 mA h g-1at 2.55 mA cm-2and 5.10 mA cm-2,respectively,and maintains a high capacity retention of84.0% after 1000 cycles at 0.13 mA cm-2,with an average cycling CE of 99.58%.

关键词： Electrolyte additive li dendrites li metal batteries liF and li3N-Rich electrode-electrolyte interphase liFePO4 cathode